Lifting jack



June 28, 1932. M. B. LUCKER LIFTING JACK Filed Dec. 14. 1927 14 13206 7175 MLZQ/TQZZ M Y F 5/ a lllllli lll Patented June 28, 1932 UNITED STATES PATENT OFFICE MILLARD B. LUCKER, BENTON HARBOR, MICHIGAN, ASSIGNOR TO AUTO SPECIALTIES MFG. 00., OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF CALIFORNIA LIFTING JACK Application filed December 14, 1927. Serial No. 240,055.

My invention relates to lifting jacks and more particularly to jacks of the type employing a hand leverfor reversing the tooth lifter bar by means of a holding dog and a lifting dog.

My present invention relates to improved details over the construction shown in my pending application Serial Number 95,035, filed March 16, 1926, patented June 10, 1930 as Patent 1,762,400 and in the patent application of Adolph Peteler, Number 61,654of October 10, 1925, patented June 3, 1930, as Patent 1,761,150 and assigned to the assignee of the present application.

One of the objects of my present invention is to provide a simplified type of jack wherein several of the parts present in the jack constructions referred to, have been eliminated and wherein the assembly operation has been made more simple.

Another object of my invention resides in providing a jack wherein the sides of the jack body are formed of pressed steel and wherein all of the operating mechanism, including the reversing mechanism, is mounted within these pressed steel side plates.

Still another object of my invention resides in pivotally mounting the holding dog on the same pivot as the handle socket, thereby eliminating the extra rivet or pivotal point and also in pivotally mounting the reversing lever on one of the rivets which holds the side plates together.

Still another object of my invention resides in providing a construction wherein only four operating parts are used in connection with the enclosing casing, which comprise the hand lever, a lifting dog, a holding dog and a reversing lever.

Still another object of my invention resides in arranging the reversing lever so as to project through an opening in the casing at a point adjacent the hand lever;

An ancillary object of my invention resides in mounting this reversing lever on the rivet about which the band which closes the front upper portion of the jack passes, thereby providing for a simplification in assembly and elimination of extra parts.

These and other objects of my invention will be apparent from a perusal of the following specification when taken in connection with the accompanying drawing, wherein:

Figure 1 is a perspective view of my improved ack.

Figure 2 is a side elevation view of the ack with certain parts broken away to reveal details of construction.

Figure 3 is a sectional-view taken substantially along the line 33 in Figure 2.

Figure 1- is a sectional view taken substantially along the line 4.4 in Figure 2.

Figure 5 is a sectional view taken substantially along the line 55 in Figure 2.

Figure 6 is a sectional view taken substantially along the line 66 in Figure 2.

Referring now to the drawing in detail, my improved jack consists of a base plate 10 of heavy sheet metal or pressed steel having two upstanding flanges 12 to which are riveted, as at 14, an integral sheet of pressed steel suitably bent to provide the two cheek or side plates 16 which, from the rivet points a 14, converge upwardly and inwardly to 'a point at approximately 18, where these two cheek plates extend vertically upward in parallel relation. The tooth lifter bar 20 is adapted to vertically slide in the way formed by the rear wall 22 of thecheek plate 16.

The operating mechanism for lifting and lowering this tooth 20, is mounted wholly between the two cheek plates 16 so that the exterior surfaces of the cheek plates 16 are entirely devoid of operating mechanism. The lifting and lowering mechanism comprises a hand lever 24 pivotally mounted on a cross-pin 26 which passes throughthe two cheek plates 16 adjacent the front thereof. This hand lever 24: is formed of sheet metal, being preferably formed by folding over a single piece of metal and riveting the same together by means of rivets 28. A handle is adapted to be inserted in the opening 32 of this socket 24.

In the present instance a holding pawl 34 is pivotally mounted on the pivot pin 26 of the manually operable lever socket 24 and this pawl is relatively long, extending from the axis 26 upwardly to the top of the casing formed by the cheek plates 16, where it is adapted to engage the teeth of the lifting bar 20. The upper portion of this pawl 34 is provided with a laterally extending lug 36 to which is secured one end of leafspring 38. The body of this spring is formed somewhat in the shape of an S and extends first downwardly to engage a lifter pawl 40 then upwardly and finally downward with the free end of the spring facing toward the front of the casing.

The lifting pawl is relatively smaller than the holding pawl 34. This lifting pawl 40 is pivotally mounted, as at 42, on the inner end of the manually operable lever socket 24 and the upper end of lifting pawl 40 is adapted to also engage the tooth lifter bar 20. The holding pawl 34 and the lifting pawl. 40 have their lower ends provided with downwardly extending arms 44 and 46 respectively. The extreme ends of these arms have laterally extending lugs 48 and 50 respectively, about which is coiled a spring 52. The ends of the laterally extending lugs 48 and 50 are peened over the coils of the spring to hold the spring vin position thereon.

' The pawl 34 is provided with a lateral cut out portion 88 in which the body of the spring may extend, the cut out being defined by lines 90 in Fig. 2, and the pawl 40 has a lateral flange 92, upon which the spring 38 may engage, extending along its upper edge, said flange being defined by the dotted line 94 in Fig. 2.

The upper portion of the casing, formed by the spaced apart cheek plates 16, is'adapted to be closed by a band of sheet steel 54, one end of which 56 curls about a rivet 58 which fastens the upper portion of the cheek plates together. The opposite end 60 of the band 54 likewise curls around the rivet 62, which not only holds the adjacent portions of the cheek plates 16 together, but in addition forms a pivotal pin having a reversing ler'er 64, which reversing lever has at its inner end, a nose66 adapted to contact with the upper portion of the spring 38. In order to permit oscillation of the reverse lever 64, the closing band 54 is cut away as at 68, to provide a slot permitting the movement of this lever. It will be seen that the free end of the spring 38 is adapted to be contacted by the nose 66 of the reversing lever 64 when shifted inwardly and downwardly so that when the nose 66 of this lever is shifted inwardly and downwardly. the spring will force the holding pawl 34 and the lifting pawl 40 against the teeth of the lifting bar 20.

The frontportion of the cheek plates 16 immediately below the socket 24, are riveted together by means of the rivet pin 70, and I preferably provide the pivot pin 26 for the lever socket 24, with a cotter pin 72 for holding it from detachment.

In order to prevent the tooth lifter bar 20 from forward tiltin movement, I provide one of the cheeks or plates 16, with a slot 74 adapted to receive an insert 7 6 of metal. This metal piece, as shown clearly in Figure 5, is formed with a shoulder 78 and a rather narrow neck 80, which passes through a smaller slot 82 in the opposite cheek plate 16. By peening this projecting end of the neck 80 of this spacing piece 76, it is held irremovably in position so that the bar cannot tilt forwardly. In addition I provide one of the cheek plates 16 with a cut out portion forming a tongue 84 which is bent inwardly as indicated in Figure 3, to engagewithin side recesses 86 extending longitudinally of the rack bar 20, by which arrangement when the bottom portion of this recess 86 strikes the inbent tongue 84, the lifter bar is held from further outward movement.

In the operation of my improved jack, when the reversing lever 64 is moved inwardly so that the nose 66 presses against the free end of spring 38, the two pawls 34 and 40 contact with the teeth of the lifting rack 20 so that when the handle 30 is moved up and down, the two pawls working against the rack 20, cause it to be raised step by step.

Reverse action is obtained by throwing the raising lever 64 in the opposite direction so that the nose 66 of this lever is freed from the leafspring 38, thus allowing this spring to float free and at the same time giving the reversing spring 52 an opportunity to function. In this position of the parts, when the handle 30 is raised, the lifting pawl 40 is lowered so that the reversing spring 52 is compressed and the holding pawl 34 is forced into engagement with the teeth of the lifting rack 20. After the load is taken by the holding pawl, the lifting pawl 40 is thrown out of engagement with the teeth of the rack 20 due to the fact that the reversing spring 52 is under a compressing strain. 7 The'handle 30 is moved down and this in turn raises the lifting pawl 40 for the next step downward.

When the lifting pawl 40 is at the top of the stroke, the reversing spring 52 is placed under tension, which causes the lifting pawl 40 to engage in the next tooth of the rack and when the load is taken by the lifting pawl, the holding pawl 34 is thrown out of engagement with the teeth of the rack and the movement downward is permitted. The coil spring 52,' during the reversing operation, functions somewhat as follows: When the handle 30 is lowered, that end of the coil spring next to the rack will tend to move away from the opposite end of the coil spring due to the fact that the inner end is attached to the innermost part of the lifting pawl which is moving upwardly. This movement tends to stretch the coil spring, thereby forcing the lifting pawl towards the teeth. At the same time this stretching of the coil spring will pull the holding pawl out of engagement with the teeth of the jack. The next operation is in the lifting of the operating lever handle 30, which exactly reverses the procedure. The first operation in going up is to compress the coil spring 52, which draws the lifting dog 40 out and the holding dog in.

It must be apparent from the foregoing, that I have provided a very compact and simple type of ack wherein all of the operating parts are mounted wholly within the two side plates of the jack thereby eliminating the necessity of placing the reversing mecha nism in a separate housing on the outside of the main side plates of the jack as heretofore. It will also be apparent that by my present construction I provide fewer parts since there is present only the usual manually operable lever, ,the usual lifting rack, the two dogs and the reversing lever. No cam lever is necessary. Furthermore, by my present arrangement of these few parts. the number of cross-pins or rivets for holding the jack plates or side plates together, is reduced to the minimum. In addition, the present construction permits of the placing of the reversing lever in a very handy position immediately in front of the operator as he is manipulating the manually operable lever. In addition, by casting the dogs with laterally extending pin 48 and 50 for receiving the coil spring 52, I provide a very simple assembly, since the coil spring can be placed over these cast lugs and the ends and lugs peened over to hold the coil spring in position. The reversing lever 64: is mounted on the rivet 62, which passes through the upper front part of the casing so that this rivet not only functions to fasten the side plates of the casing together at this point, but also provides a means for holding in place the closing band 54; and for providing a pivotal pin for the reversing lever 64. Likewise I provide a very simple spacing construction by using the piece 76 and by passing it through the slots in the cheek plates and peening the head 80 of this spacing member 76 into the opening 82 on one of the side plates. This spacing member prevents the rack bar 20 from tilting forward.

As a result of my construction, it will be seen that I have provided alight, pressed steel jack wherein the upright portion or housing portion of the jack is formed of a single piece of pressed steel folded or doubled upon itself so as to completely house all of the working parts of the ack'so that by this change I am enabled to eliminate the usual cover plate for the reversing mechanism and the screws or rivets for holding this plate in position, and furthermore, I am enabledto eliminate the necessity of punching out large holes in the side of the cheeks, shown in prior constructions, which holes were necessary to enablethe assembler to assemble the pawls. By pivoting the holding pawl on thesame cross-pin or rivet 26 as the handle socket 24 is pivoted, I am enabled to eliminate an extra rivet in the construction. One of the importantimprovements over heretofore existing jack constructions, is the elimination of hitherto important parts. Thus I have provided a very simple, effective and rugged type of reversible jack.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a lifting jack, the combination of a base and an upright, the latter having spaced apart portions forming a housing for a vertically reciprocable toothed lifting bar, a manually operable lever pivotally mounted between said spaced portions forming the upright, a lifting dog pivotally mounted on the inner end of said manually operable lever and having a depending arm, a holding dog pivotally mounted on the pivotal axis of said manually operable lever, said holding dog being relatively longer than the lifting dog and extended above to engage the teeth of the rack bar, a leafspring carried by the upper end of said holding dog and depending downwardly to engage the lifting dog, a reversing lever pivotally mounted between said parallel portions of the upright and at the upper portion thereof, and having a nose within said portions adapted to engage" said spring when said nose is moved into one position whereby to force said dogs into engagement with the teeth and to free said spring when the nose is moved into another position, said holding dog also having a depending arm and a coil spring interconnecting the depending arms of said holding dog and said lifting dog.

2. In a lifting jack, the combination of a base and an upright formed of sheet steel provided with spaced apart cheek plates, a toothed lifter bar housed and guided in the rear portion of said upright, said check plates having registering slots adjacent and in front of the path of movement of said lifter bar,

one of said slots being of less width than the other slot, and a spacing piece passing through the larger slot and having a neck extending into the smaller slot, the head of said neck being peened against the outer face of the adjacent cheek to hold the spacing piece in position, and mechanism mounted between said cheeks of the upright and co-operating with the toothed lifter bar for lifting or lowering said bar in step by step movement, said mechanism comprising a manually operable lever pivoted in said upright, a holding dog pivoted to the axis of said manually operable lever, a lifting dog pivotally mounted to said lever, resilient means extending between said lifting dogs for urging the upper ends of said lifting dogs in opposed directions, spring means for urging the upper portions of said dogs toward said lifter bar and means for removing the pressure of said spring whereby to permit said resilient means to actuate the dogs upon movement of the lever.

In witness whereof, I have hereunto subscribed my name.

MILLARD B. LUOKER. 

